Method of making paper



Patented Dec. 15,- 1931 UNITED STATES PATENT OFFICE ARTHUR G. DRESHFIELD, OF KALAMAZOO, MICHIGAN, ASSIGNOR TO PAPER MAKEBS CHEMICAL CORPORATION, OF KALAMAZOO, MICHIGAN METHOD OF MAKING PAPER No Drawing. Application filed. July 25,

The main object of this invention is to provide an improved method of making paper which results in a very substantial saying in sizing material and also which expedltes the paper making operation and results 1n a very desirable product.

A further object is to provide a method of makin paper which results in economy of manufacture without detracting from the product.

Objects pertaining to details and economies of myinvention will definitely appear from the description to follow. The invention 1s defined in the claims.

In practicing my method of making paper I employ a size preferably in the form of a bone dry impalpable powder and consisting I of a resin saponified with an alkali. This size I introduce into the stock, preferably while it is being agitated in the beater, in the dry or powder form. The fixative, such as alum in the preferred practice, has previously been added to the dry size and this in the proportion of 1 part of dry size to 2 parts of alum. However, it will be understood by those skilled in the art that the proportion of the precipitant may be and is commonly varied according to the judgment of the paper maker, the result desired, and the conditionof the water used.

In the event that the stock is colored in the beater it is commonly not desirable, at least with certain colors, to add all of the alum or precipitant when the size is introduced as that may result in uneven coloring, since alum and certain other precipitants employed in paper making act as a fixative for the colormg.

The size used is that described in my application for Letters Patent filed concurrently herewith Serial No. 47 0,7 69, filed July 25,

1930, and is preferably prepared by the method of that application. Broadly stated, it is prepared by saponifying a suitable resin,

such as commercial rosin, by cooking with a saponifying agent such as soda ash Where soda ash is employed the proportions may be 100 pounds rosin, 18 pounds soda ash and pounds water. These proportions, however,

50 may be very considerably varied depending ployed although the best results are attained 1930. SerialNo. 470,770.

'on the strength of the alkali and whether soda ash or some other saponifying agent is employed such as caustic soda, ammonium hydroxide, sodium silicate, caustic potash, potassium carbonate, or the like.

The cooked material is thoroughly desiccated and preferably reduced to. an impalpable powder, a satisfactory method being that of my said application, which consists of atomizing the treated resin in the path of a current of hot air. The size falls to the bottom of the drying chamber in the form of a powder. Other methods of desiccating may be emwhen the size is introduced into the stock in the form of an impalpable powder and in substantially a bone dry condition. Less size is required than where the size is introduced in'the form of an emulsion or wet aste, as is common practice, on account of t e greater efiiciency of my improved size, which I have found to run as high as 300 percent. The resulting paper is not only very effectively sized but is of very uniform quality.

Therefore, my improved method not only results in a superior product but in a very substantial saving, both in the amount of size necessary and in handling and introducing to and mixing with the stock.

Having thus described my invention what I claim as new and desireto secure by Letters Patent is: I

1. The method of making paper consisting of adding to the stock a size in the form of an impalpable powder, and consisting of a resin saponified with an alkali and alum in the proportion of one part of the size to two parts of the alum, the alum and the size having been previously mixed in dry condition. Y

-2. The method of making paper consisting of adding to the stock a size in the form of a powder, and consisting of a rosin saponified with an alkali, and a precipitant, the 95 precipitant and size having been previously mixed in dry condition.

3. The method of making paper consisting of adding to the stock while in the beater a size in the form of a powder, and consisting of a rosin saponified with an alkali, and a precipitant.

4. The method of making paper consisting of adding to the stock a size in desiccated condition, and consisting of a rosin saponified with an alkali, and a precipitant, the size and precipitant having been previously mixed in dry condition.

5. The method of making paper consisting of adding to the stock a size consisting of a desiccated saponified rosin and a precipitant.

6. The method of making paper consisting of adding to the stock while in the beater a size in the form of powder, and consisting of a rosin saponified with an alkali.

7. The method of making paper consisting of adding to the stock a desiccated size consisting of a rosin and a saponifying agent.

8. The method of making paper consisting of adding to the stock a saponified resin size and precipitant in the form of an impalpable powder.

In witness whereof I have hereunto set my hand.

ARTHUR G. DRESHFIELD. 

